Clamshell bucket



1952 w. A. OLSON 2,617,211 CLAMSHELL BUCKET Filed July 21, 1947 3 Sheets-Sheet 1 Fig. 2.

O I O O Inventor I 1 O I 0 J1 William A. Olson mu away 19% 81s Nov. 11, 1952 w. A. OLSON CLAMSHELL BUCKET 5 Sheets-Sheet 2 Filed July 21, 1947 William A Olson B] Ma Nov. 11, 1952 w. A. OLSON CLAMSHELL BUCKET S'Sheets-Sheet 3 Filed July 21, 1947 I u z'entor William A. Olson Patented Nov. 11, 1952 UNITED STATES PATENT OFFICE CLAMSHELL BUCKET WilliamA. Olson, Wheatl'and, Mo.

Application J uly 21, 1947, Serial No. 762,411 a claims, (c1. s7-.-1s5) i This invention relates generally to excavating.

equipment, and more particularly to .a clamshell bucket comprising two main sections, each sectionhaving a scoop and a pair oflateral operating levers, a novel cable guard mounted on the.

shaft connecting the levers, and a complement of bucket-operating cables and pulleys, the general arrangement of the device and the construction of the scoop members including features of improved and novel character.

A primary object of this. invention is to provide a clamshell bucket construction in which the cables are protected against undue wear, and

prevented from snarling during the normal operation of the bucket.

Another object of this invention is to provide a centrally andvertically disposed cable guide of novel character securedto the shaft connecting the levers and extending upwardly to enclose operating cables.

Another object of this invention is to improve the construction of the scoop members in clamshell buckets of this character so as to facilitate the manufacture thereof and to make the more easily worn out portions replaceable.

Still another object of this invention is to provide a clamshell bucket which is relatively inexpensive and practicable to manufacture, extremely simple and convenient to use, and which is generally sturdy, efiicient, and durable in service.

With these objects definitely in view, this invention resides in certain novel features of construction, combination and arrangement of parts and portions as will be hereinafter described in Q the specification, particularly pointed out in the appended claims; and illustrated in the accompanying drawings which form a material part of this application, and in which:

Figure 1 is a sideelevational view of this improved clamshell bucket;

- Figure 2 is another side elevational view, on a reduced scale, of this bucket;

Figure 3 is a top plan view of the bucket when the same is in-fully opened position, the cables being shown as disposed when in taughtened position, the cable guard member being vertically disposed and the cable spider associated with the cables for opening the bucket, being shown immediately above the said cable guard member;

' Figure 4 is a side elevational View of the bucket when in partially opened position, the fully opened position of the bucket being illustrated in dash lines, the figure being taken on line 4-4 in Figure 3;

Figure 5 is a transverse vertical sectional view of the cableguard member, the fair lead and the upper end of this cable member, together with portions of cables and the above mentioned cable spider, the figure being taken on the line 5-5 in Figure 3; and

Figure 6 is a transverse vertical sectional view, taken on the line 6-6 of Figure 3, the Figures 5 and 6 being both fragmentary in character.

. comprises an inverted U-shaped tubular member,

in two substantially similar sections, each section having a scoop; generally indicatedby the nu;- meral I0, dissimilar lever portions I2 and I4 pivoted together on the terminal portions of a shaft.

I6 and; similar upwardly extending lever portions,

I8, a cable guard generally indicated by the nue meral 2,0, and a complement of operating; cables and pulleys as will be hereinafter described morev fully.

Each scoop section I0 is comprised of an arcu-.

ate back plate 22, generally triangular side. plates 2 which: are secured to the said back plate; by angles 26 and a replaceable nose plate28 having terminal portions upwardly bent and marginally riveted to the side plates 24 and to the back plate 22, the general shape of the scoop being substantially conventional.

The lever I2 is constructed of two inflexible strap portions disposed in parallel relationship with lower end portions 30 riveted to the side plate 24, as indicated at 32, and upwardly extending portions 34 of unequal length straddling the corresponding said upwardly extending-lever portions I8 and rigidly secured to the said portions I8, the bolts 36 being used to secure these parts together and simultaneously to mount a pair of spaced cross arms 38 to and betweenthe upwardly extending portions of each of the levers I2, it being understoodthat the majority of the elements of. this. invention are provided in dupliicate. The pair of levers. I 4 are each of single strap construction and the lower end an of each of these levers is secured by bolts or rivets to the side plate 24 of the other section oilthe scoop Ill. The upper end of the lever I4 is provided with a plate 42 and thelower edge 44 of this in Figure l. Auxiliarypmeans to limit the-opening of the bucket is provided on the other side of the bucket and comprises a portion 48 at the lower end of the upwardly extending portion of the outer strap member, and the upper edge portion 50 of the corresponding side plate 24, this side plate being out backso that the edge 50 contacts the portion 48 at the same time as the edge A l contacts the portion 46.

The guard member, generally indicated at 2B,

havingthe lower ends of the vertical arm portions thereof pivotally secured to the shaft I6, as indicated at 52 in Figure 2. The sides of these lower portions are extended to provide for terminal attachment of short. shafts 54 which may be of bolt form and to act as guards for pulleys 56 which are mounted on the shafts 54 between these guard portions which are best illustrated at 58 in Figure 4. The cross member 80 of the cable guard is apertured as at 62, at each side thereof and these apertures register with the upper end of the tubular vertical arm portions of the cable guard. A fair lead comprised of parallel pairs of rollers 64 and 68 guides a cable 68 from an overhead drum or reel, not shown in the drawings, to the cross member 80, downwardly to the pulley 10 which is freely rotatably mounted in a bracket 12 pivotally mounted on the shaft IS. A plurality of sleeves H are secured on the shaft [6 to properly space the pivot members of the bracket 12. and the lower end members of the cable guard 20.

It will be noted that the cable 68 is entrained through the pulley I0, thence through one of the pulleys 16 which are rotatably mounted between the corresponding pairs of cross arms 38, and this cable extends from this pulley 16 to a pulley 18 which is one of a pair of similar pulleys rotatably mounted between the other pair of cross arms 38. the end of the cable 68 being ordinarily secured to an eye 88 which is rigidly secured to one of the cross arm members 38, as illustrated in Figure'3.

It should be noted that the cable 88 may be entrained about all four pulleys represented in the drawings at 18 and 18, the use of the extra pulleys having been found to be an advantage for certain types of work. A preferred method of mounting the pulleys I6 and 18 comprises the provision of vertically disposed supporting bracket members 82 which are rigidly secured to the cross arm members 38, and a cable guard plate 84 is provided on the outside of each of these pulley assemblies.

Obviously, the cable 68 is used to close the bucket and to lift the same, and two pairs of cables 86 are connected with the bucket to open the same. The cables 86 depend from a spider 88 which is operated by a single cable 98. The cables 86 are threaded through the apertures 62 downwardly through the vertical arms of the cable guard 28 and entrained around the pulleys 56 and thence outwardly around the pulleys 92 which are freely rotatably mounted in brackets 94 secured to the upper edges of the arcuate plates 22 of the scoops. The ends of the cables 88 are secured, as indicated at 96, to apertured members 98 integrally secured to the upper outer edges of the cross arms 38. It is preferred that each of the pulleys 16, 18 and 92 should be provided with cable guide members of plate character as illustrated at 108;

The operation of this invention will be clearly understood from the foregoing description of themechanical details thereof, when taken in connection with the above recitation of the objects sought to be achieved by this invention, but in recapitulation, it may be noted that the bucket will be suspended by the cable 68 and will be lowered and raised thereby, while the opening and closing of the buckets are provided for by upwardly tensioning of the cables 86 and by gravity, respectively. This method is exceptionally well adapted for use under conditions requiring the bucket to be lowered into the material sought to be moved with the scoop of the bucket, closed, although the device is also well adapted for use when it is desirable to lower the bucket in open position and thereafter allow gravity to close the 4 bucket at the commencement of the elevation thereof.

It is believed that the foregoing description will enable persons skilled in the art to manufacture and use this invention and further description is therefore deemed unnecessary.

Though there has been shown a particular embodiment of this invention, this application is not limited to this particular embodiment, but it is desired to include in the scope of this invention, the construction, combination and arrangement of parts and portions substantially as set forth in the appended claims.-

Having described the invention, what is claimed as new is:

1. A clamshell bucket comprising two main sections, each section having a scoop and a pair of lateral operating levers, a shaft extending through and between intermediate portions of said levers, the levers on each side of the bucket being pivoted upon terminal portions of said shaft, a cable guard secured on said shaft and. normally vertically disposed, a bracket pivoted on said shaft, and a complement of bucket-operating cables and pulleys, said levers having connecting cross arms adjacent the ends of the levers remote from the scoops, said cables being terminally secured to said cross arms, and said cable guard extending upwardly beyond the cross arms when the scoops are closed together, said pulleys being mounted on the lower end of said cable guard, on said bracket, on the upper outer edges of .said scoops, and on said cross arms, said cables including a pair of bucket-opening cables each entrained through one of said pulleys on the lower end of said cable guard and one of the pulleys on the upper outer edges of the scoops and terminally connected to the lever of the opposite scoop, and a bucket-closing and lifting cable entrained through a pulley on said bracket and through at least one of the pulleys on one of said cross arms and through at least one of the pulleys on the other cross arm and terminally secured to said one cross arm.

2. The device as defined in claim 1 wherein said cable guard is of inverted U-shape and has tubular vertical arms, the cross memberof the cable guard being vertically apertured and having a fair lead for the bucket-opening and bucketclosing and lifting cables. 1

3.- The device as defined in claim 1 wherein said cable guard is of inverted U-shape and has tubu-' lar vertical arms, the cross member of the cable guard being vertically apertured and having a fair lead, said fair lead guiding said bucket-opening and bucket-closing and lifting cables, and a spider connecting said bucket-closing and lifting cables with a single cable.

' WILLIAM A. OLSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 221,705 Seward Nov. 18, 1879 500,818 Price July 4, 1893 707,484 Wirsing Aug. 19, 1902 1,571,838 Hutson Feb. 2, 1926 1,578,724 Gregg Mar. 30, 1926 1,909,867 Olson May 16, 1933 FOREIGN PATENTS Number Country Date 569,369 France Jan. 6, 1924 

